Receiving apparatus for pneumatic-despatch systems.



H. D. WATERHOUSE. RECEIVING APPARATUS 11011 PNEUMATIG DESPATGH SYSTEMS.

, APPLIOATION FILED O(1T.23,A 1907.

Patented 11111117; 1911.

THE-'Nakms'rerens co.. WASHINGTON. n. c4

HAROLD D. WATERI-IOUSE, OF NORFOLK DOWNS, MASSACHUSETTS, ASSIGNOR, :BY MESNE ASSIGNMENTS, TO AMERICAN PNEUMATIC SERVICE COMPANY, 0F BOSTON, MASSACHUSETTS, A CORPORATION OF DELAWARE.

RECEIVING APPARATUS FOR PNEUMATIC-DESPATGI-I SYSTEMS.

Specification of Letters Patent.

Patented Mar. r, 1911.

Application led October 23, 1907. Serial No. 398,713.

To all whom it may concern:

Be it known that I, HAROLD D. WATER- r-IoUsn, a citizen of the United States, residing at Norfolk Downs, in the county of Norfolk and State of Massachusetts, have invented certain new and useful Improvements in Receiving Apparatus for Pneumatic- Despatch Systems; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appcrtains to make and use the same.

The invention relates to pneumatic despatch systems, and more especially to apparatus for receiving carriers at the delivery end of the tube through which they are transmitted.

The invention is especially applicable to systems for transmitting comparatively large carriers, such, for instance, as are employed for sending mail matter from one station to another, and its object is to provide a receiving apparatus of such a character that carriers of different weights shall be uniformly and properly delivered without danger of injury to the carrier or apparatus.

OneWof the prlncipal features of the invention consists in providing means for reducing or relieving the pressure Vback of the carrier before it reaches the discharge end of the transmission tube, and regulating pressure back of the carrier in accordance with the resistance offered by the carrier after it has passed the point where the reduction in pressure takes place. The transmission tubing is arranged or is provided with devices to effect a retarding or slowing down of the carrier after it passes beyond the pressure reduction point and since the retarding means will act differently upon carriers of dierent weight the reduction in pressure back of the carrier is varied by the regulatingmeans to compensate for this difference in order that the carriers may be properly and uniformly delivered.

It is preferred to so construct the retarding devices that the heavier carriers will be retarded to a greater extent than the lighter ones, and in this case the devices for regulating the pressure back of the carrier are constructed to secure a higher pressure' the heavier the carrier. This insures a substantially uniformrdelivery of the carriers and also causes the pressure to build up back of a carrier in case it becomes stuck in the retarding devices, so that the carrier will be forced out of the transmission tube.

Further features of the invention relate to the construction of the retarding devices. These devices comprise an upwardly curved tube forming the end of the transmission tube, and an open guide chute extending upward from the discharge end of the transmission tube and reversely curved to deliver upon a substantially horizontal receiving table. rlhe curved end of the transmission tube and the curved open guide chute act to retard the carrier by reason of their vertical arrangement, and also by reason of their curvature, the centrifugal force of the carrier as it passes around the curves increasing the friction between the carrier and the tube and chute. The upwardly curved end of the transmission tube acts to retard and slow down the carrier while it is still acted upon by the propelling forceY of the air behind it, and the open guide chute acts to complete the retarding or slowing down of the carrier after it has passed from the discharge cnd of the transmission tube and is no longer subjected to any impelling force. The discharge of the carrier from the transmission tube may therefore be insured, and the carrier may still be delivered at the receiving table, with practically no speed, or with any desired speed.

The features above referred to, as well'as the further features of the invention which relate to the form and arrangement of the devices in which it is preferred to embody the broader feaures of the invention will be understood from an inspection of the accompanying drawings, in which- Figure 1 is a side elevation, partly in section, of a receiving apparatus embodying the features of the invention in the forms in which I prefer to use them, and Fig. 2 is an enlarged sectional detail showing the discharge end of the transmission tube and the devices for regulating the pressure back of the carrier.

In the construction shown in the drawings, the delivery end of the transmission tube is curved upward at B to form a retarding chamber through which the carriers pass to the discharge end B1 of the transmission tube. up the bend B, the speed of the carrier is As the carrier travels Y retarded by reason of the friction due to the centrifugal force, and also by reason of the upward direction in which the carrier is forced to travel. On passing through the discharge end or mouth B:L of the transmission tube the carrier passes into the vertically arranged chute D which is made up of rods so that it forms an open chute where the carrier is free from the act-ion of any propelling force. As the carrier passes up and around the curved chute D it is retarded until it is delivered onto the receiving table E at the proper speed.

In order that the speed with which the carrier passes through the delivery end of the transmission tube and is discharged from the mouth of the tube may be reduced, and may be controlled to secure a uniform delivery of carriers of different weight, the transmission tube is provided with a bypass A forming an exhaust ata point in advance of the delivery end of the tube. This bypass communicates with a pipe H and the escape of air through the bypass and pipe is controlled and regulated by a valve K arranged at the discharge end or mouth of the pipe. It is evident that the less pressure there is behind the'carrier the slower will be its travel along the transmission tube, and the more effective will become the bend B in reducing its speed. By regulating the amount of air discharged through the bypass A, any desired portion of the pressure behind the carrier after it has passed this bypass may be relieved, and the speed at which the carrier will be delivered from the mouth of the transmission tube under normal conditions may be controlled. Since, the weight of the carriers which may be transmitted through the apparatus varies widely, the adjustment of the exhaust which would secure the proper speed for one weight of carrier would not be pro-per for securing the required speed with a different weight of carrier. In order to secure the substantially uniform delivery of the carriers, the apparatus is therefore provided with means for automatically regulating the exhaust through the bypass to compensate for the variation in the pressure required to force the carriers of different weight through the delivery portion of the transmission tube at the proper speed.

The devices for automatically regulating the exhaust in the apparatus shown consists of a diaphragm L mounted in a diaphragm casing L1 and connected with the valve K through a rod K1. The valve K is held in its extreme open position by means Lof a spring N acting upon the under side of the diaphragm L. The amount of air which is discharged through the bypass A and pipe H when the valve K is in its extreme open position may be regulated by means of a nut L2 screwed onto the upper however,

end of the valve rod K1, and engaging the upper end of the diaphragm sleeve L3. The chamber within the diaphragm casing above the diaphragm L is connected through a pipe M with the pipe H, in which the pressure is substantially the same as the pressure back of the carrier after it has passed the bypass A.

The valve K is adjusted so that the proper amount of air will exhaust through the bypass A and pipe H to secure the proper delivery of an empty carrier. When a loaded carrier is being transmitted through the transmission tube, more pressure will be required to force it up the inclined bend B, and it will therefore tend to slow up in the bend to a greater extent than an empty carrier. Owing tothe restricted exhaust at the valve K the pressure will build up in the tube back of the carrier and in the pipe H. This pressure will be transmitted through the pipe M to the diaphragm L, forcing said diaphragm downward so as to slightly close the valve K. This movement of the valve further restricts the exhaust, causing a further building up of the pressure behind the carrier so that the carrier is forced up and out of the tube B. The building up of the pressure back of the carrier in that part of the transmission tube beyond the bypass A will be proportional to the resistance offered by the carrier to the discharge of air through the tube and the closing of the valve K will be automatically regulated to secure substantially the same speed of travel through the tube with carriers of different weight.

Since the resistance offered to the movement of a carrier through the retarding bend B causes a closing vof the valve K,`and a building up of the pressure back of the carrier, the lodging or sticking of a carrier in the transmission tube beyond the bypass A would cause a complete closing of the valve K and a rapid building up of the pressure until the carrier was discharged or a maximum pressure produced.

In order to avoid accidents by reason of the building up of the pressure in the transmission tube beyond the safety point, a safety device is provided for relieving the pressure within the tube when said pressure exceeds a predetermined amount. This safety device may be of any suitable character, and in the construction shown is in the form of a diaphragm O arranged to close a bypass leading from the chamber above the diaphragm L to the chamber below said diaphragm. When the pressure within the transmission tube increases beyond a certain amount the diaphragm @will burst, opening' communication between the cha-1nbers on opposite sides of the diaphragm L so that the pressure is equalized on opposite sides of the diaphragm. The spring N will then open the valve K to its full extent, thus relieving the pressure Within the transmission tube.

The transmission tube `B and the exhaust pipe H may discharge directly into the atmosphere it' desired, but it is preferred to connect the discharge end of the tube and pipe With a tube I leading to the air compressing` mechanismrso that the air passing through the transmission tube may be used over and over again, and also in order that there may be no objectionable blasts of air delivered into the receiving room.

The exhaust and regulating valve K may be arranged at any desired point, but it is preferred to arrange this valve and the controlling devices adjacent to the discharge end of the transmission tube in the manner indicated in the drawings, since with this arrangement the valve and controlling devices are conveniently situated Where they may be inspected and regulated by the operator, and the safety device is also arranged -Where it is conveniently accessible.

Having explained the nature and object of the invention, and described one form of apparatus in which it maybe embodied, What I claim is 1. A receiving apparatus for pneumatic despatch systems, having, in combination, a transmission tube and means operating to automatically reduce the pressure back of the carrier at a point in advance of the delivery end of the tube, in accordance With the resistance offered by the carrier after passing said point, substantially as described.

2. A receiving apparatus for pneumatic despatch systems, having, in combination, a transmission tube, retarding means at the end of the tube, means for reducing the pressure back of the carrier in advance of the retarding means, and means operating to automatically regulate the pressure back of the carrier to compensate for variations in the retarding action, substantially as described.

3. A receiving apparatus for pneumatic despatch systems, having, in combination, a

transmission tube, retarding means at the end of the tube, and means operating to automatically control the pressure back of the carrier to compensate for variations in the retarding action, substantially as described.

4. A receiving apparatus for pneumatic i determined amount,

despatch systems, having, in combination, a transmission tube, a retarding chamber at the end of the tube, an exhaust outlet from said tube in advance of said chamber controlled by the retarding of the carrier, substantially as described.

5. A receiving apparatus for pneumatic despatch systems, having, in combination, a transmission tube, an exhaust outlet in advance of the delivery end of the tube, and a device automatically controlling the exhaust to compensate for variations in the resistance oiered by the carrier after passing the exhaust outlet, substantially as described.

6. A receiving apparatus for pneumatic despatch systems, having, in combination, a transmission tube provided at its delivery end with a reta-rding chamber, an exhaust outlet from said tube in advance of said chamber, means for controlling the exhaust by the pressure back of the carrier after it has passed the exhaust outlet, substantially as described.

7. A receiving apparatus for pneumatic despatch systems, having, in combination, a transmission tube, an exhaust outlet in advance of the delivery end of the tube, and means for controlling the exhaust by the pressure back of the carrier after it has passed the exhaust outlet, substantially as described.

8. A receiving apparatus for pneumatic despatch systems, having, in combination, a transmission tube provided with an up- Wardly curved delivery end, and an open guide chute at the mouth of the transmission tube arranged in a vertical reverse curve, substantially as described.

9. A receiving apparatus for pneumatic despatch systems, having, in combination, a transmission tube, an exhaust outlet in advance of the delivery end of the tube, means for controlling the exhaust by the pressure in the tube beyond the exhaust outlet, and a safety device for relieving the pressure in the tube when it exceeds a presubstantially as described.

In testimony whereof I aiiix my signature, in presence of tivo Witnesses.

HAROLD D. WATERHOUSE. Witnesses:

IRA L. FISH,

ANNIE C. RICHARDSON.

Copies of this patent may be obtained for five cents each,

by addressing the Commissioner of Patents,

Washington, D. C. 

